Field of the Invention
The present invention relates to a method of detecting a small cell on the basis of a discovery signal.
Related Art
3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) that is an advancement of UMTS (Universal Mobile Telecommunication System) is being introduced with 3GPP release 8. In 3GPP LTE, OFDMA (orthogonal frequency division multiple access) is used for downlink, and SC-FDMA (single carrier-frequency division multiple access) is used for uplink. The 3GPP LTE adopts MIMO (multiple input multiple output) having maximum four antennas. Recently, a discussion of 3GPP LTE-A (LTE-Advanced) which is the evolution of the 3GPP LTE is in progress.
As set forth in 3GPP TS 36.211 V10.4.0, the physical channels in 3GPP LTE may be classified into data channels such as PDSCH (physical downlink shared channel) and PUSCH (physical uplink shared channel) and control channels such as PDCCH (physical downlink control channel), PCFICH (physical control format indicator channel), PHICH (physical hybrid-ARQ indicator channel) and PUCCH (physical uplink control channel).
Meanwhile, in a next-generation mobile communication system, it is expected that a small cell of which a cell coverage radius is small is added in macro cell coverage.
However, since it is expected that such a small cell is deployed with a high density, there is a disadvantage in that interference may be increased. To solve this problem, it can be improved so that the small cell is temporarily off and is then on according to an interference amount.
However, since a user equipment (UE) cannot detect the small cell in a state where the small cell is temporarily off, there is a problem in that a fast connection cannot be achieved even if the small cell is on again at a later time.